Problem: In her chemistry class, Emily took 4 exams. Her scores were 98, 82, 90, and 90. What was her average score on the exams?
Explanation: The average is the sum of her scores divided by the number of scores. There are 4 scores and their sum is $98 + 82 + 90 + 90 = 360$ Her average score is $360 \div 4 = 90$.